1. Field of the Invention
The present invention generally relates to a friction clutch for a motor vehicle, the friction clutch having a flywheel and a clutch housing. The flywheel and the clutch housing are connected to one another by means of a cylindrical wall disposed near the radially outer portion of the clutch housing. The cylindrical wall can extend in a ring-shaped manner about the axis of rotation of the flywheel. The friction clutch can also generally include a clutch plate having friction linings in its radially outer area, and an application plate or pressure plate which can be pressed towards the clutch plate by means of an application spring.
2. Background Information
German Patent No. 38 02 955 A1 discloses a motor vehicle friction clutch with a clutch housing, which clutch housing extends toward the flywheel in the form of a cylindrical wall formed in the circumferential area of the clutch housing. With the free end of this wall, the clutch housing encloses the flywheel, and is connected to the flywheel by means of screws. By means of its cylindrical wall, the clutch housing encloses a clutch plate, which clutch plate is located between the flywheel and an application plate or pressure plate. The clutch plate is designed in the radially outer area to support friction linings. Pressure can be applied to the above mentioned application plate toward the clutch plate by means of an application spring, which application spring is mounted on the clutch housing.
A friction clutch with a clutch housing designed in this manner takes up little space in the radial direction. However, there are essentially no measures in a friction clutch of this type which would make possible an engagement or disengagement of the clutch by means of only a relatively low expenditure of force.
German Patent No. 42 39 289 A1 also discloses a motor vehicle friction clutch with a clutch plate. In the circumferential area of the clutch plate, there is a friction lining on each of the two sides of a lining spring system. One of these friction linings is adjacent to a flywheel, while the other friction lining faces an application plate. The application plate can be pressed towards the clutch plate by means of an application spring, which application spring is mounted on the clutch housing. The application spring, the application force of which is kept constant by means of an adjustment device which acts in the event of wear, is active during engagement or disengagement in the opposite direction to the lining spring system. As such, during the engagement or disengagement process, the two spring forces can at least partly offset one another. Consequently, but at the cost of a rather expensive design and construction, the clutch can be engaged or disengaged with a relatively small expenditure of force.
On this friction clutch, the clutch housing has a wider portion in the manner of a flange in the area in which it is connected to the flywheel, and thus takes up a comparatively large amount of radial space, with respect to the outside diameter of the clutch plate.
German Patent No. 25 42 692 C2 discloses that, on the clutch plate of a friction clutch, it is possible to rivet a backing or base on a support part, and to glue the friction linings to the backing. Since the friction linings are generally located in the circumferential area of the clutch plate, a disadvantage can be that the mass moment of inertia of the clutch plate can be relatively high due to the backing.